Copa Libertadores round of 16 is set: Here are the winners, losers

Palmeiras went through as group winners and will be one of the favourites in the Copa Libertadores round of 16.

The group phase of the Copa Libertadores kicked off at the start of March with a hard-fought game between Deportes Iquique of Chile and Guarani of Paraguay. On Thursday, the two sides met again, bringing the phase to a close and duelling for the last available slot in the knockout phase - and a goalless draw was good enough to send the Paraguayans through. With the last 16 teams now set, here are some of the headlines from what has happened the past three months.

The Big-Name Failures

Four former champions have bitten the dust -- including the inaugural winners (and five-time champions) Penarol of Uruguay. This is perhaps not a major surprise. Penarol's last triumph was back in 1987. Since then, given Uruguay's population of about 3.4 million, Uruguayan club football has suffered badly in a globalised context. Penarol have become used to group phase elimination -- this is the fifth consecutive time it has happened. But 15 goals conceded in six games tells the story. The 2016-17 Penarol side are one of the worst in the club's glorious history.

The last Copa Libertadores winners also fell. Atletico Nacional of Colombia lost their first three games and could not fight their way back. This, too, is not a great surprise. Nacional have paid the price for success in contemporary South American football -- putting their best players in the shop window. Those who watched the performance of Ajax centre-back Davinson Sanchez in the Europa League final will understand. Between -- and only between -- February and July last year he was first-choice in the Nacional team. Then Europe beckoned. Nacional were also in a strong group, which ended the participation of Estudiantes of Argentina, whose fourth and last title win came in 2009. They were workmanlike but uninspired, and suffered from the late start to this year's Argentine league, leaving them short of match fitness when they endured early defeats.

Perhaps the most surprising -- and certainly the most dramatic -- first-round failure was that of Rio de Janeiro giants Flamengo. The club have only one title, in 1981. But with an expensively assembled squad, fans were convinced that this would be their year. The home games, all wins, began with the crowd holding up a giant mural, 1981 on one side, 2017 on the other. But Flamengo lost all their away games, the consequence of a slow defensive unit that sat too deep and invited pressure. It all unravelled in the last few minutes of their final group game, and a club that has accumulated plenty of recent Libertadores frustrations has another one to lament.

10 countries began, only six remain

Atletico Nacional were not the only Colombian side to fail to make the cut. Medellin's last-day win away to River Plate was a case of too little, too late. And Santa Fe could not find the goal they needed to get themselves ahead of The Strongest of Bolivia. And so, in one of the biggest shocks of the group phase, Colombia has suffered a first-round wipeout -- the first time it has happened since 2009.

Much less surprising is the early end to the participation of clubs from Peru (for the fourth year running and the sixth in the last seven) and Venezuela (for the seventh time in the last eight campaigns). Given the recent success of Chile's national team, many will be surprised to see that Chilean clubs suffered a wipeout. But this has become normal in the Libertadores. It is the third consecutive year, and the fourth in the last five, that no club from Chile has made it through to the round of 16.

Luiz Otavio scored the winning goal against Lanus, but was ineligible and thus Chapecoense forfeited the points.

Debutants with dignity

None of the four teams playing their first Libertadores campaign managed to make it through to the last 16. Sport Boys Warnes of Bolivia found it all a little much, and were one of three teams to fail to win a single game. But they can content themselves with a good memory; going into the last 20 minutes away to Brazil's Atletico Mineiro, one of the tournament favourites, Sport Boys Warnes were 2-1 up.

Zulia of Venezuela have an even better recollection. They won away to three-time champions Nacional of Uruguay, the team with the best defensive record in the competition. A new club, Zulia showed they might be stronger in years to come.

But the other two debutants did particularly well. Atletico Tucuman of Argentina, a provincial club that had to fight their way in dramatic fashion through two qualifying rounds, showed a consistent concern with playing attractive football and won many admirers with the manner of their displays, even when they lost 3-1 away to Brazilian champions Palmeiras.

And Chapecoense could hardly have done better. The Brazilian club, of course, lost almost their entire playing and coaching staff in an airplane crash at the end of November. Under new coach Vagner Mancini they have rebuilt well, playing pragmatically within their limitations. Their campaign had its up and downs -- perhaps the biggest up and the biggest down came together. Last week they won 2-1 away to Lanus of Argentina, a magnificent result. But Chapecoense did it with a player who should not have been on the field. Defender Luiz Otavio should have been serving a suspension. He scored the winning goal.

There were clear flaws in the way the club were informed that the player was ineligible. But they were told before the kickoff, foolishly picked him anyway, and were stripped of the three points they had won on the field. The club are appealing, but as it stands the decision to select Otavio to play against Lanus is the difference between bold elimination and heroic qualification.

Group form no guide for knockout round

In previous years, the knockout phase got underway the week after the end of the group matches. This year is different, with the competition going all the way to the end of November rather than being squeezed into the first few months.

There is now a gap of well over a month (until July 4) for the first leg of the next round -- and then a gap of more than a month (until Aug. 9) for the return games. Recent form, then, matters less this time round. Teams that have reached a peak to guarantee their place may be past their peak by the time the action resumes. And then there is the potentially unsettling effect of the opening of the European transfer window.

In one sense, though, the competition has become more predictable. The new format has given more space to Brazil and Argentina, who between them provide 10 of the last 16 teams. The Ecuadorian pair of Barcelona and Emelec might put up some resistance; Nacional of Uruguay have a tight defensive unit; and Bolivia's The Strongest are feared opponents at the extreme altitude of La Paz. But it would be a real surprise if the 2017 version of South America's premier club crown does not end up on the head of a team from one of the continent's big two footballing nations.

Tim Vickery covers South American football for ESPN FC. Follow him on Twitter @Tim_Vickery.